Imidazolinylpyridine and quinoline compounds, their use as herbicidal agents and methods for the preparation thereof are described in U.S. Pat. No. 4,638,068; 4,758,667 and 4,798,619. Quinoline carboxylates and dicarboxylates useful as intermediates in the preparation of herbicidal imidazolinyl quinoline compounds are described in U.S. Pat. No. 4,843,162.
Herbicidal 5-heterocyclic-2-(2-imidazolin-2-yl)pyridines and methods of use thereof are described in copending U.S. patent application Ser. No. filed concurrently herewith.
It is an object of the present invention to provide 5-heterocyclic-pyridine-2,3-dicarboxylate esters useful as intermediates in the preparation of 5-heterocyclic-2-(2-imidazolin-2-yl)pyridine herbicidal agents and processes for the preparation thereof.